Context

• Recently on Girgaum chowpatty a famous tourist spot in South Mumbai saw big, black oil-emanating balls lying on its sandy beach.

What are tarballs?

• The tar balls are crude-oil forms from which petrol is extracted.
• Tar balls are dark-coloured, sticky balls of oil that form when crude oil floats on the ocean surface.
• They are formed by weathering of crude oil in marine environments.
• They are transported from the open sea to the shores by sea currents and waves.
• Tarballs are usually coin-sized and are found strewn on the beaches. However, over the years, they have become as big as basketballs and can weigh as high as 6-7 kgs.

Do tarballs indicate an oil spill?

• Most of the times, the presence of several tarballs indicate an oil spill.
• However, its annual occurrence on the west coast during the monsoon has led marine biologists and experts to demand an investigation in the matter.
• Experts have urged authorities to take stricter vigil and check if ships are dumping burnt oil waste off the western coast of India.
• Oil-well blowouts, accidental and deliberate release of bilge and ballast water from ships, river runoff, discharges through municipal sewage and industrial effluents” also leads to the formation of tarballs.

Are tarballs harmful?

• Tarball pollution is a major concern to global marine ecosystem.
• Tarballs that travel towards the coast can get stuck to the fishing nets installed in the sea, making it difficult for fishermen to clean.
• In addition, it could affect marine life, especially filter feeders like clams and oysters.
• Coming in contact with a small amount of the greasy oil is not harmful, but if an individual is sensitive to hydro-carbons found in crude oil, then the contact area should be washed with soap and water.

How are they disposed?

• Microbes such as bacteria and fungi are known to be associated with tarballs.
• They presumably play an important role in tarball degradation and some are potential human and animal pathogens.

Source:Indian Express